In the field of medicine and laboratory science, the automation of medical laboratory procedures and the like has become necessary in order to cope with the massive amounts of testing and other procedures which are now required. At one time, it was possible to count bacteria colonies in a culture sample by eye to determine the number of colonies in a specimen. However, automation of this type of procedure has become essential.
Additionally, while a simple count of the number of colonies in a specimen can be carried out manually, it is often desired to select only a particular area of the sample and restrict the count to that area. Sometimes, various size and density minimums must also be set whereby only the count of colonies greater than these minimum levels are to be included.
It is furthermore oftentimes necessary to obtain an area measurement of a complex shaped object as, for example, a cell or a component of a cell, such as its nucleus. Accurate measurements of this type have heretofore been obtained by time-consuming and costly methods. Such variations and specialized counting further necessitates the need for automation in the field of microbiological counting.
Colony counters are already available which attempt to satisfy the above-mentioned needs. By way of example, U.S. Pat. No. 3,811,036 entitled "MICROBIOLOGICAL COLONY COUNTER," issued on May 14, 1974, and assigned to the assignee of the present invention, describes a basic automatic colony counter which places a flag on each colony detected and displays the output. U.S. Pat. No. 3,757,299, entitled "METHOD AND APPARATUS FOR MEASURING THE SIZE OF ZONES OF INHIBITION IN AN ASSAY MEDIUM," issued on Sept. 4, 1973, and assigned to the assignee of the present invention, describes various types of pattern recognition and measuring systems for certain types of colonies and similar microbiological items to be detected. Also, U.S. Pat. No. 3,922,532, entitled "CELL COUNTER," issued on Nov. 25, 1975, and assigned to the assignee of the present invention, describes an improved counter which can count objects in a sample and includes both size and density discrimination.
While the aforementioned apparatus, as well as other prior art devices, provide for automation of the field of microbiological counting and displaying, these units do not present the versatility needed in such apparatus in order to permit its use in a variety of application. For example, the particular area of the sample which is scanned remains constant in such apparatus and there is no means provided for modifying the size and/or shape of the area being scanned.
Similarly, with many such devices, the holder of the sample covers a portion of the sample itself and, therefore, the entire area cannot be scanned. As a result, the count scanned is not a complete count for the entire sample and no compensation is provided for this type of automatic counting. Additionally, it is frequently desired to provide additional measurements such as the percent of area covered by the colonies or the absolute area of the colonies. Prior art devices have not provided for such capabilities.
As a result, despite the success of many of the apparatus, complete versatility and use for many applications have thus far not been provided.